[LUCENE-2093] Use query-private scope instead of shared Term->TermInfo cache

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 4.0, 6.0
• Component/s: core/search
• Lucene Fields: New
• Assignee: Unassigned
• Reporter: Michael McCandless
• Created: 24/Nov/09 11:45
• Updated: 28/Aug/22 12:15
• Resolved: 11/Sep/12 16:53

Description

Spinoff of LUCENE-2075.

We currently use a shared terms cache so multiple resolves of the same term within execution of a single query save CPU. But this ties up a good amount of long term RAM...

So, it might be better to instead create a "query private scope", where places in Lucene like the terms dict could store & retrieve results. The scope would be private to each running query, and would be GCable as soon as the query completes. Then we've have perfect within query hit rate...